Tension-responsive control for strip material reeling



Aug. 27, 1968 P. J. CUNNINGHAM TENSION-RESPONSIVE CONTROL FOR STRIP MATERIAL REELING 4 Sheets-$heet 1 Filed Jan. 6, 1967 Aug. 27, 1968 P, J. CUNNINGHAM TENSION-RESPONSIVE CONTROL FOR STRIP MATERIAL REELING 4 Sheets-Sheet 2 Filed Jan. 6. 1967 7, 1968 P, J. CUNNINGHAM 3,398,914

TEN5ION-RESPONSIVE CONTROL FOR STRIP MATERIAL REELING Filed Jan. 6, 1967 4 Sheets-Sheet 5 INVENTOR. ZWz/KKJKM A/M aA M 1968 P. J. CUNNINGHAM 3,393,914

TENSION-RESPONSIVE CONTROL FOR STRIP MATERIAL REELING Filed Jan. 6, 1967 4 Sheets-Sheet 4 i N VEN TOR.

United States Patent 3,398,914 TENSION-RESPONSIVE CONTROL FOR STRIP MATERIAL REELING Patrick J. Cunningham, Fullerton, Calif., assignor to Consolidated Electrodynamics Corporation, Pasadena, Calif., a corporation of California Continuation-impart of application Ser. No. 511,463, Dec. 3, 1965. This application Jan. 6, 1967, Ser. No. 621,375

20 Claims. (Cl. 24275.43)

ABSTRACT OF THE DISCLOSURE A strip tension control mechanism for a strip material reeling device in which a belt driven pulley is connected to a reel for strip material, strip material from the reel passing a tension sensing roller biased into a selected position adjacent the reel when tension in the strip has a desired value. The roller is coupled to a belt idler roller so that when the strip tension at the sensing roller is greater than the desired tension, the idler roller is moved to slack the belt on the reel drive pulley. Where the roll is a supply reel from which strip material is withdrawn at a constant rate, a brake is associated with the pulley and is coupled to the sensing roller so that when the strip tension at the sensing roller is less than the desired tension, the brake is engaged with the pulley.

Cross-reference to related applications This application is a continuation-in-part of application Ser. No. 511,463, filed Dec. 3, 1965, now abandoned. Commonly-owned application Ser. No. 485,768, filed Sept. 8, 1965, is referred to as illustrative of a system in which the present invention has utility.

Background of the invention Field of the invention.This invention relates to a control mechanism for a strip material reeling device, the control mechanism being responsive to the tension in the strip material to regulate operation of the reeling device so that breakage of the strip material is prevented.

Motion picture projectors commonly include a film supply reel, a film take-up reel, and a film drive mechanism located adjacent the projection lens system along the film path between the reels. In small projectors wherein the capacity of the supply and take-up reels is limited, the film drive mechanism determines the speed at which the film is moved between the reels; in such projectors the takeup reel is driven at a constant rate and the supply reel normally free-wheels. In a projection system like that disclosed in copendin-g, commonly-owned application Ser. No. 485,768, filed Sept. 8, 1965, wherein the capacities of the supply and take-up reels are large, a mechanism for regulating the tension in the film adjacent each reel is required to prevent the film from breaking. In a large capacity reel, the effective radius of the reel between reelfull and reel-empty conditions varies considerably, with the result that the torque arm of the moment applied to the film from a reel driven at a constant angular velocity varies correspondingly. As a result, the tension generated in the film adjacent the supply or take-up reel varies considerably and can reach a value greater than the tensile strength of the film, unless some control mechanism responsive to the tension in the film is provided for the reeling devices in the projector.

This invention provides a simple, effective and novel control mechanism for the reeling devices of a large capacity motion picture projection system. The control mechanism is responsive to the tension in the motion picture film adjacent the film supply and take-up reels. The

control mechanism markedly reduces the variation in tensile forces applied to the film and assures that the film will not be broken by sudden increases in the tension in the film. The tension in the fil-m adjacent the reels is maintained essentially constant, thereby reducing cyclic loadings on other components of the projection system. Also, by maintaining the film tension essentially constant adjacent the take-up reel, the capacity of the take-nip reel is maximized; wide variations in the tension 'of the film fed to the take-up reel cause the film to bunch and gather on the reel, 'thereby reducing the film storage capacity of the reel. Moreover, the same structure used in the supply reel control mechanism is used in the take-up reel control mechanism, thereby reducing manufacturing costs.

Summary of the invention This invention provides a strip tension control apparatus for a strip material reeling device including a reel adapted to receive a quantity of strip material. The control apparatus includes a drive pulley coupled to the reel and a belt engaged with at least a portion of the periphery of the pulley. Means are provided for driving the belt to rotate the pulley for driving the reel in a selected direction. A roller, around which strip material is passed in response to rotation of the reel, is provided, together with means mounting the roller adjacent the reel for rotation about its axis and for translation relative to the reel. Resilient means are coupled to the roller mounting means for biasing the roller into a selected position when the strip material passing around the roller has a selected tension therein. The control apparatus also includes linkage means operably coupled from the roller mounting means to the belt. The linkage means is operable for slacking the belt on the pulley when the strip material has a tension greater than the selected tension.

Brief description of the drawing The above-mentioned and other features of the present invention are more fully set forth in the following detailed description of a presently preferred embodiment of the invention, this description of the invention being presented with reference to the accompanying drawing wherein;

FIG. 1 is an elevation view of the supply side of a film supply and take-up cassette showing a tension responsive control apparatus according to this invention;

FIG. 2 is an elevation view of the take-up side of the cassette shown in FIG. 1 showing the tension responsive control apparatus for the take-up reel;

FIG. 3 is an elevation view, with parts broken away for clarity of illustration, of the supply side of another reeling installation according to this invention;

FIG. 4 is an elevation view, with parts broken away for clarity of illustration, of the take-up side of the installation shown in FIG. 3; and

FIG. 5 is an elevation view of the take-up side of the installation shown in FIG. 3.

Description of the preferred embodiments Referring initially to FIGS. 35 which depict a presently preferred reeling installation 60* in a motion picture entertainment system of the type described in application Ser. No. 485,768, the installation includes a hollow partition 61 mounted by hinges 62 to structural member 63 of a passenger aircraft. The partition has a supply side 64 and an opposite take-up side 65. Coaxial supply and take-up pulleys 66 and 67 are mounted adjacent corresponding sides of the partition and are arranged to co.- axially receive and be coupled to supply and take-up film reels 68 and 69, respectively.

Each pulley has a reel receiving shaft 70 extending coaxially thereof away from the partition, each shaft having an externally threaded free end. Each pulley also carries a pair of projecting dogs 70 which cooperate with corresponding apertures in the reel for keying the reel to the pulley. The shaft cooperates with a center hole in the appropriate reel. Each reel is secured on its supporting shaft by a clamp bar 71 (FIG. threaded onto the end of the shaft, the bar being secured from disengaging rotation relative to the shaft by suitable spring-loaded detent balls carried by the bar adjacent its end which engage detent recesses in the reel. Each reel, therefore, is securely engaged coaxially of its drive pulley and cannot slip angularly relative to the pulley.

Supply and take-up drive capstans 72, 73 respectively are coaxially mounted on the respective sides of the partition for rotation about an axis parallel to but spaced from the axis about which the pulleys turn. The capstans are powered by a capstan drive unit 74, including a motor 75, mounted to the top and interior of the partition, the capstans being mounted on a common shaft 76 extending through the partition.

With reference to FIG. 3 which illustrates the tension control mechanism on the supply side of partition 61, a belt 77 is engaged between capstan 72 and pulley 66 so that the belt engages a portion of the periphery of the pulley. The belt also engages an idler roller 78 which is located outside the loop formed by the belt. The idler roller is rotatably mounted to the median portion of an idler support lever 79 which is pivoted at 79' to the partition adjacent capstan 72. The tautness of the belt against supply pulleys 66 is regulated by the position of idler roller 78.

As film 80 (preferably 16 mm. motion picture film) is withdrawn from supply reel 68, it passes between a first idler 81 and guard 82 roller pair, around a tension sensing roller 83, and then between a second idler 84 and guard 85 roller pair disposed adjacent the first pair near the top of the partition. A guard roller 86 is associated with the tension sensing roller. The guard rollers are provided to assure that the film is retained in engagement with the adjacent larger idler or tension sensing roller and does not jump from the desired film path as the mechanism is operated.

The tension sensing roller and its guard are mounted outwardly of the outer diameter of supply reel 68 on the unsupported end of a substantially straight bellcrank arm member 87 which is pivoted to the partition at 88 adjacent the belt about midway between 'the supply pulley and the supp-1y capstan.

Film 80 is extracted from the supply reel at an essentially constant rate by a motion picture projector (not shown) located remote from the supply reel along the film path. In the preferred use of this invention, the projector which extracts film from the supply reel is the first of the several projectors contemplated by the system described in aforementioned copending application, Ser. No. 485,768.

Bellcrank member 87 is biased by a tension spring 89 into a predetermined position angularly of its pivot when the film passing the tension sensing roller is subject to a preselected value of tension. The spring is connected between the bellcrank member and the partition.

A brake shoe 90 is located adjacent the supply pulley for pivotal movement about a pivot 91 for engagement of a braking face 92 of the shoe with the periphery of the supply reel. The shoe is biased about its pivot into engagement with the supply pulley of a spring 93. The shoe braking .face is located into the direction of rotation of the supply pulley relative to pivot 91.

A first rigid link member 94 is pivoted between the brake shoe and the bellcrank member which carries the tension sensing roller. The pivot of the link member to the bellcrank is at 95, a shot distance from pivot 88 relative to the distance of the tension sensing roller from pivot 88. As a result, a high mechanical advantage is provided between the bellcrank and the brake shoe. The support lever for belt idler roller 78 is also linked to the bellcrank via a second rigid link member 96 pivoted between the end of a lever 79' adjacent the supply pulley and link member 94 adjacent pivot 95. Preferably, the pivotal connection of the second link member to lever 79 is adjustable via a slot 97 in the lever.

When reel 68 is essentially empty and the bellcrank is in its predetermined position relative to pivot 88, the brake shoe lightly engages the supply pulley and the tautness of belt 77 between the capstan and the supply pulley, as regulated by the position of the belt idler roller, is sufiicient that the pulley is driven from the capstan -via the belt against the drag of the brake shoe at a rate essentially equal to the rate at which film is extracted from the supply reel; for condition in which the reel is not essentially empty, pulley 66 slips relative to belt 77. As the tension of the film between the supply reel and the extracting device is varied, either by reason of normal variance of the quantity of film stored upon the reel or because of a speed-up or slow-down of the extracting device, these tension variations are sensed by roller 83 and manifested as a change in the angular position of the bellcrank carrying roller 83.

The linkage system between the sensing roller, the belt idler roller, and the brake shoe is arranged to maintain the tension in the film substantially constant between conditions of supply reel-full and supply reel-empty. As the tension in the film adjacent the reel is decreased from the desired value, the bellcrank moves clockwise about pivot 88. This motion of the bellcrank is reflected in the brake becoming increasingly effective against the supply pulley and the belt becoming decreasingly efiective (because the tautness in the belt is decreased) to drive the pulley against the drag of the brake. As a result, the supply reel slows down to match the rate of extraction of film from the reel, thereby reestablishing the desired tension in the film. Conversely, as film tension increases the bellcrank moves counterclockwise about pivot 88, thus increasing the driving effectiveness of the capstan on the pulley as the belt becomes more taut, and decreasing the action of the brake on the pulley. Thus, the supply reel is driven faster until the film extraction rate is matched and the desired film tension is restored. At all times positive control is had over the rotation of the supply reel, a very desirable feature where the capacity of the supply reel is large and the supply reel has relatively great angular momentum. If film extraction is suddenly interrupted, the supply reel is brought to a rapid stop. Conversely, the supply can be bought very quickly to the desired rate of rotation when the system is started.

To guide the supply reel in its rotation relative to the partition, a pair of rollers 98 are mounted to the supply side of the partition for engaging a flange 99 of the reel adjacent the partition. The reel has an opposite flange 100 disposed parallel to flange 99 and outwardly thereof relative to the partition. A pair of small diameter rollers 101 are mounted to the partition adjacent the periphery of the supply reel for engaging the respective opposing faces of flanges 99 and 100 just inwardly of the periphery of the reel near idler roller 81. Rollers 101 assure that the reel flanges are spaced apart a distance greater than the width of the film strip in the area of the reel through which the film passes from the reel to idler roller 81. Thus, the reel flanges are prevented from dragging on the film strip and producing variations in the tension in the film at sensing roller 83. As a result, the operation of the tension controlling mechanism described is not subject to cyclic loadings attributable to reel-to-film drag, but instead operates smoothly to maintain the film tension substantially constant.

FIG. 4 shows the film tension control mechanism provided on take-up side 65 of partition 61. The bulk of the structure of this control mechanism is identical to the structure of the supply reel tension control mechanism, and thus primed reference numerals corresponding to those used above and appearing in FIG. 3 are used in the description below. It will be observed from FIG. 4 that no brake is provided for the take-up pulley; this portion of the tension control mechanism is not required in this embodiment of the invention in view of the metering device 105 (FIG. 5) which is provided to meter film to take-up reel 69 at an essentially constant rate. It will also be observed that the pivot of bellcrank arm member 87' to the partition is coaxial to the mounter of member 87 to the opposite side of the partition. Film idler rollers 81 and 84' are associated with a common guard roller 102, and the bias of bellcrank 87' to its predetermined position is provided by parallel springs 103. Two springs are provided as a safety measure; if one should break, the take-up mechanism will continue to function.

If the film tension sensed by roller 83' is too great relative tothe preselected tension value defined by the geometry of the mechanism shown in FIG. 4, the tautness of belt 77 on the take-up pulley is relaxed, so that the driving effectiveness of capstan 73 on the take-up reel via the belt is reduced and the reel movement is slowed by the film itself. On the other hand, if the film tension falls below the desired level, the belt tautness is increased and the driving effectiveness of the capstan on the takeup reel is similarly increased.

Metering mechanism 105 for the take-up reel is shown in FIG. 5 mounted to the structure of the aircraft above the partition; the partition is assumed to be in its position for operation. It should be understood that the structure shown in FIG. 5 pertains to the preferred use of the invention in connection with a multi-projector film display system. The metering mechanism is provided to simulate, at the film take-up station, another projector relative to the actual last projector in the display system.

Film is supplied to the take-up station from the last projector through a film guide duct 106, past an idler roller 107, around a film drive sprocket 108 having two idler rollers 109 associated with it, and then past a translatory and rotatable control roller 110 biased by a spring 115. The sprocket is driven from a motor 111. The control roller is coupled to a switch (not shown) which is effective to turn off the metering mechanism when and as long as the film tension at the control roller is below a desired level. After leaving the control roller, film 80 passes two idler rollers 112 and 113 to idler roller 84 of the take-up station.

' A motion picture film supply cassette 10, provided in another embodiment of the invention in place of partition 61 and shown in FIGS. 1 and 2, includes a central partition 11 which divides a housing 12 into a supply reel chamber 13 and a take-up reel chamber 14. A film supply reel 15 is mounted in the supply reel chamber for rotation about an axle 16. Motion picture film 17 is fed from the reel via an idler roller 18 and two pinch rollers 19 through an opening 20 in the housing to a motor drive unit 21 coupled with the cassette exteriorly of the supply and take-up reel chambers. The motor drive unit includes a motor (not shown) which drives a sprocket wheel (not shown) engaged with the film for driving the film through the motor drive unit and onto a projection station at a constant velocity. The motor drive unit also includes a second sprocket wheel (not shown) for moving film from a remote projection station into the take-up reel chamber at a constant rate in a manner similar to the operation ofmetering mechanism 105 described above.

The film supply reel carries a coaxial drive pulley 23 disposed between the reel and partition 11. A circumferential groove 24 is formed in the pulley. A drive belt 25 is engaged in the groove around a portion of the periphery of the pulley, with a fixed axis idler roller 26, a drive capstan 27, and a tension roller 28. The capstan is rotated at a constant rate from the motor drive unit via a shaft 29 (see FIG. 2) which extends from the drive unit within the partition. The belt is coupled to the supply reel pulley so that the reel rotates counterclockwise (as seen in FIG. 1) about axle 16 in response to counterclockwise rotation of the capstan. The capstan is secured to a shaft 30 which extends through partition 11 to mount the drive capstan for the film take-up reel described hereinafter.

Belt tension roller 28 is disposed within the loop defined by belt 25 and is rotatably mounted to the free end of an arm 31 pivotally mounted to the partition by a pin 32. A tension spring 33 is coupled between the arm and the partition for biasing the arm in such a manner that the tension roller is urged to move against the belt, thereby keeping the belt taut and snugly engaged in the groove of pulley 23. Preferably spring 33 applies a force of from about 6 to about 10 ounces upon arm 31.

A generally quadrangular brake shoe 35 is mounted to a pivot pin 36 carried by partition 11 at a location adjacent the periphery of pulley 23 within the loop defined by belt 25. The brake shoe is configured to be engaged in braking relation to the pulley in the sides of groove 24. Pin 36 is so located relative to reel axle 16 that the brake shoe moves clockwise about the pin into engagement with the pulley. The shoe is configured so that, when it is engaged with the pulley, the portions thereof in contact with the pulley are displaced into the direction of rotation of the pulley from a line connecting axle 16 and pin 36.

As film is reeled from reel 15, it passes around a portion of the periphery of an idler roller 38 located next adjacent the reel between the reel and idler roller 18. Roller 38 is rotatable about an axle 39 which is carried by a bellcrank arm member 40 pivotally mounted to the cassette partition by a pin 41. The bellcrank mounts roller 38 for translation relative to the axis of reel 15. A tension spring 42 is connected between the bellcrank and the partion for urging roller 38 into a predetermined position tition for urging roller 38 into a predetermined position relative to pulley 23 when a selected amount of film is present between the reel and idler roller 18 and this film has a predetermined tension therein. Preferably spring 42 exerts a force of from about 6 to about 10 ounces upon the bellcrank arm member.

A drag link member 44 interconnects the bellcrank arm member and the brake shoe. The connection of the drag link to the bellcrank arm member is by way of a slot 45 in the drag link and a pin 46 carried by the bellcrank. The other end of the drag ling is pivotally connected to the brake shoe by a pin 47. A tension spring 48 is connected between the drag link adjacent pin 47 and the partition for urging the end of slot 45 opposite from pin 47 into engagement with pin 46 and for imparting a clockwise moment to the brake shoe about its mounting pin 36. Preferably spring 48 exerts upon the drag link a force of from about 8 to about 10 ounces.

A length of braided wire 49 interconnects the drag link and tension roller arm 31 from adjacent pin 47 to adjacent the tension roller.

Pins 41, 46, 47 and 32 are arranged on the partition relative to reel axle 16 in such a manner that, when the proper amount of film exists between the reel and idler roller 18 and is under the proper tension so that roller 38 is in its predetermined position, brake shoe 35 rides lightly against the walls of pulley groove 24 and tension roller 28 maintains belt 25 taut.

If reel 15 is overdriven by its constant speed drive relative to the rate at which film is withdrawn through slot 20, then the quantity of film between the reel and idler roller 18 increases and the tension in this film falls below the level desired. Spring 42 then urges bellcrank arm member 40 counterclockwise about pin 41 allowing spring 48 to move the brake shoe into braking engagement with the reel drive pulley, thereby slowing the rotation of the reel until proper tension has been restored in the film adjacent the reel. During such movement of the bellcrank, the drag link moves to the right as seen in FIG. 1. The action of the tension roller upon the belt is unchanged during such movement of the drag link since braided Wire 49 is not capable of transmitting compression forces to arm 31.

On the other hand, if reel should be underdriven by its constant speed drive mechanism relative to the rate at which film is drawn through opening 20, the tension in the film adjacent the reel will be sharply increased. In such event, arm 40 is moved clockwise about pin 41, thereby moving the drag link to the left. Such movement releases the brake shoe from the reel drive pulley and eases the force of engagement of the tension roller with the belt, thus initially allowing the drum to rotate faster. In the event, however, that this adjustment is not sufficient to restore the desired condition of film tension and the bellcrank continues to move clockwise about pin 41, continued leftward movement of the drag link moves the belt tension roller 28 sufficiently via wire 49 that the film pulls the reel around about axle 16. In such a case, the reel free-wheels until the proper film tension is restored.

From the foregoing, it is apparent that the structure described controls the tension present in film 17 adjacent reel 15 to such an extent that breakage of the film is prevented.

If the path of the film to roller 38 from reel 15 were constant, i.e., fixed relative to axle 16, the control mecha nism described would maintain the tension of the film constant within narrow limits. It is apparent, however, that the direction of the film path from the reel to roller 38 relative to the direction of the film path from the roller to idler roller 18 varies as the amount of film stored on the reel varies. As a result, the tension maintained in the film when the reel is full is about twice the tension value maintained in the film when the reel is nearly empty. Were the control mechanism described not present, the ratio of tensions maintained would be about 5:1 since the tension produced in the film would be a function of the effective radius of the reel.

FIG. 2 shows the structure mounted to the other side of cassette partition 11 in take-up reel 51 mounted to an axle 16, an extension of the same axle which carries the supply reel. It will be observed that the structure in the take-up reel chamber is identical to structure provided in the supply reel chamber, and thus primed reference numerals corresponding to those used above and in FIG. 1 are used to identify these structural elements and features. The only difference is that belt is looped once so that take-up reel 51 rotates counterclockwise in response to rotation of capstan 27 in a clockwise direction as seen in FIG. 2. Pins 32, 36 and 41 shown in FIG. 2 are axial extension of the pins shown in FIG. 1 and thus these elements do not have primed numerals associated therewith in FIG. 2.

It will be observed that the loop formed in belt 25' between capstan 27' and pulley 23' causes brake shoe to engage the pulley at a location displaced along the direction of pulley rotation from a line between axle 16 and pin 36.

Film is fed into the take-up reel chamber through an opening 53 in housing 12 at a constant rate from motor drive unit 21. If reel 51 should be underdriven relative to the rate of film input to the chamber (and this is a rare condition), then bellcrank arm member 40' moves clockwise about pin 41 slacking wire 49' so that tension roller 28' exerts its maximum effectiveness against belt 25 so that capstan 27' is most effective to drive pulley 23'. Such motion of the bellcrank allows brake shoe 35- to be engaged with the pulley in response to the action of spring 48'. The brake shoe, however, is kicked out of engagement with the pulley by reason of the relation of the brake shoe to the direction of rotation of the pulley. This clockwise movement of the brake shoe about pin 36 is absorbed by the lost-motion connection provided between the drag link and the bellcrank by slot More commonly, reel 51 is overdriven relative to the film advance mechanism provided in motor drive unit 21. In such an instance, the bellcrank is moved counterclockwise about pin 41 so that tension roller 28' is moved to loosen belt 25 about the reel pulley, thereby reducing the effectiveness of the belt in driving the reel. In extreme cases, the belt is loosened sufficiently that the reel is made freewheeling about axle 16 and the film itself acts to brake the reel.

It will be noted that idler roller 26 is present only in the supply reel chamber and has no counterpart in the take-up reel chamber. The idler roller is provided in the supply reel chamber so that belt 25 has the same wraparound capstan 27 as belt 25' has around capstan 27'. Accordingly, belts 25 and 25' are identical and equal values of tension are maintained in the belts so that both control mechanisms have substantially identical response characteristics.

From the foregoing it is apparent that the supply reel control apparafus is essentially identical to the take-up reel control apparatus. As a result, the film cassette is simple and economical to construct. Also, since identical structural arrangements are used, servicing of the apparatus is simple.

The cassette described above finds utility in the film projection system described in the copending, commonlyowned application identified above. It should be understood, however, that the reeling device control mechanisms described herein have utility apart from the system described. Also, it will be understood that modifications and alterations including variations of the geometrical relationships described, may be made in the abovedescribed structure without departing from the spirit or the scope of this invention. Accordingly, the foregoing is not to be regarded as limiting the scope of this invention.

What is claimed is:

1. Strip tension control apparatus for a strip material reeling device including a reel adapted to receive thereon a quantity of strip material, the control apparatus comprising a reel drive pulley coupled to the reel, a belt engaged with the reel drive pulley around at least a portion of the periphery thereof, a belt drive member engaged with the belt for driving the belt to rotate the reel in a selected direction, means for driving the belt drive member at a constant effective peripheral velocity, a sensing roller around which strip material is passed in response to rotation of the reel in said selected direction, means mounting the roller adjacent the reel for rotation about its axis and for translation relative to the reel, resilient means coupled to the roller mounting means for biasing the roller into a selected position when the strip material passing the roller has a selected tension therein, and linkage means operably coupled from the roller mounting, means to the belt for slacking the belt on the reel drive pulley when the strip material has a tension greater than a selected tension.

2. Apparatus according to claim 1 wherein the reel is a take-up reel and including means for feeding strip material to the reel at a substantially constant rate.

3. Apparatus according to claim 1 wherein the roller mounting means comprises an arm pivotally supported for angular movement about a point fixed relative to the axis of pulley rotation and mounting the roller thereto at a location spaced from said point.

4. Apparatus according to claim 1 wherein the linkage means includes a belt tension roller mounted for movement into and out of engagement with the belt, the belt being slack on the pulley when the tension roller is disengaged from the belt.

5. Apparatus according to claim 4 including means for biasing the tension roller into engagement with the belt.

6. Apparatus according to claim 5 wherein the linkage means includes a pivoted member mounting the belt tension roller, and means coupling the pivoted member and the sensing roller mounting means effective to cause the 9. pivoted member to move with said mounting meansin response to movement of said mounting means when strip material adjacent has a tension greater than the selected tension, and ineffective to cause the pivoted member to move with said mounting means when strip material adjacent the reel has a tension less than the selected tension.

7. Apparatus according to claim 1 wherein the selected direction of reel rotation is selected sothat strip material is iinreeled from the reel, and means for unreeling strip material from the reel at a substantially constant speed.

8.- Apparatus according to claim 1 including pivotal brake means mounted adjacent the pulley for movement into and out of braking engagement with the pulley, the brake means being arranged to engage the pulley at a location displaced against the direction of pulley movement from a line between the axis of pulley rotation and the location of pivotal support of the brake means, and the linkage means includes means operably coupled from the roller mounting means to the brake means for moving the brake means into engagement with the pulley when the strip material adjacent the roller has a tension therein less than the selected tension.

9. Apparatus according to claim 1 wherein the selected direction of reel rotation is selected so that strip material is reeled onto the reel pivotal brake means mounted adjacent the pulley for movement into and out of braking engagement with the pulley; the brake means being arranged to engage the pulley at a location displaced in the direction of pulley movement from a line between the axis of pulley rotation and the location of pivotal support of the brake means, and the linkage means includes means operably coupled from the roller mounting to the brake means for moving the brake means into engagement with the pulley when the strip material adjacent the roller has a tension therein less than the selected tension.

'10. Apparatus according to claim 9 including a lost motion connection in the linkage means between said arm and said brake shoe member.

11.Apparatus according to claim 1 including brake means mounted adjacent the pulley for movement into and out of braking engagement with the pulley, and the linkage means includes means operably coupled from the roller mounting means to the brake means for moving the brake means into braking engagement with the pulley when the strip material adjacent the roller has a tension therein less than the selected tension.

12. Apparatus according to claim 11 wherein the brake means comprises a brake shoe members pivotally mounted for movement into and out of said braking engagement, and the linkage means includes a link member pivotally interconnected between the brake shoe member and the roller mounting means.

13. A supply and take-up station for motion picture film and the like comprising a partition having opposite supply and take-up sides, axle means extending coaxially from opposite sides of the partition, a film supply reel and a film take-up reel rotatably mounted to the axle means adjacent the respective sides of the partition, coaxial and rotatable supply reel drive and take-up reel drive pulleys coupled to the respective reels, a belt in each chamber engaged around a portion of the periphery of the respective pulley, shaft means extending coaxially from opposite sides of the partition at a location spaced from the axle means, a capstan on the shaft means adjacent each side of the partition with which a respective 'belt is engaged for driving the respective reel in response to rotation of the shaft means, the belts being arranged so that the reels rotate in the same direction about the axle means, identical bellcranks pivotally mounted one to each opposite side of the partition as coaxially aligned locations, a film tension sensor roller rotatably mounted to each bellcrank at corresponding locations from locations of pivotal support of the bellcranks, the film passing around the respective rollers in moving to and from the respective reels, re-

silient means connected to each bellcrank for biasing the tension sensor rollers into corresponding selected positions when the film engaged with the rollers has a selected tension therein, a belt tension roller mounted to each opposite side of the partition for movement intoand out of engagement with the respective belt, and substantially identical linkage means adjacent each side of the partition interconnecting the respective bellcrank and beltv tension roller for moving the belt tension roller connected'thereto out of tensioning engagement with the adjacent belt when the film engaged-with the adjacent tension sensor roller has. a tension greater than the selected tension.

14. Apparatus according. to claim 13 wherein each pulley is mounted coaxial with its adjacent reel.

15. Apparatus according to claim 14 including a brake shoe member pivotally mounted to the supply side of the partition for movement into and out of engagement with the adjacent drive pulley, and the linkage means for the supply side includes means interconnecting the adjacent bellcrank and the brake shoe member for moving the brake shoe member into engagement with the adjacent pulley when the film engaged with the supply side tension sensor roller has a tension therein less than the selected tension.

16. Apparatus according to claim 15 including a takeup side brake shoe member identical to the supply side brake shoe member mounted coaxially thereof to the take-up side, and wherein the linkage means for the takeup side is identical to the linkage means for the supply side.

17. Apparatus according to claim 16 wherein the supply side brake shoe member engages the supply reel drive pulley at a location displaced against the direction of rotation of the pulley from a line between the axle means and the location of pivotal support of the brake shoe member, and the take-up side brake shoe member engages the take-up reel drive pulley at a location displaced in the direction of rotation of the pulley from a line between the axle means and the location of pivotal support of said brake shoe member.

18. Apparatus according to claim 17 including a lost motion connection in the linkage means between each brake shoe member and the adjacent bellcrank.

19. Strip tension control apparatus for a strip reeling device including a reel adapted to receive thereon a quantity of strip material, the control apparatus comprising a reel drive pulley, means coupling the reel and the reel drive pulley and ar anged so that a constant relation always exists between the angular velocities of the reel and the reel drive pulley during rotation thereof, a belt engaged with the reel drive pulley around at least a portion of the periphery thereof, means for driving the belt to rotate the reel in a selected direction, a sensing roller around which strip material is passed in response to rotation of the reel in said selected direction, means mounting the roller adjacent the reel for rotation about its axis and for translation relative to the reel, resilient means coupled to the roller mounting means for biasing the roller into a selected position when the strip material passing the roller has a selected tension therein, and linkage means operably coupled from the roller mounting means to the belt for slacking the belt on the reel drive pulley when the strip material has a tension greater than a selected tension.

20. Strip tension control apparatus for a strip reeling device including a reel adapted to receive thereon a quantity of strip material, the control apparatus comprising a reel drive pulley coupled to the reel, a belt frictionally engaged with the reel drive pulley around at least a portion of the periphery thereof, a belt drive member engaged with the belt for frictionally driving the belt to rotate the reel in a selected direction, means for driving the belt drive member at a constant effective peripheral velocity, a sensing roller mounted adjacent the reel for rotation about its axis and for translation relative to the reel around which strip material ispassed in response to rotation of the reel in said selected direction, and resiliently biased linkage means operatively coupled to the-roller and to the belt for biasing the roller'into a selected position relative to the reel when strip material passing the roller has a selected tension therein, for biasing the belt into a's'elected degreeof frictional reel driving engagement with the reel drive pulley when the sensing roller is in its" selected position; and for varying the degree of reel driving frictional engagement between the belt and the reel drive pulley in response to movement of the sensing roller from the selected position thereof thereby to vary 12. the angular velocity of the reel in response to variations in strip material tension.

References Cited FRANK I. COHEN, Primary Examiner.

NATHAN L. MINTZ, Assistant Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,398,914 August 27, 1968 Patrick J. Cunningham It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 3, line 68, "of" should read by line 74, "shot" should read short Column 4, line S, cancel "a"; line 1?, "condition" should read conditions Column 6, line 38, cancel "tion for urging roller 38 into a predetermined position"; line 49, "ling" should read link Column 7, line 41, after "in" insert take-up reel chamber 14. This structure includes a film line 52, "extension should read extensions Column 9, line 25, "reel" should read reel line 48, members" should read member line 71, "as

should read at Signed and sealed this 3rd day of March 1970.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Commissioner of Patents Edward M. Fletcher, Jr.

Attesting Officer 

